Insight for Sunday 4 March 2012
Didymo began it's invasion of waterways in this country in 2004.
It's a type of alga and has spread rapidly throughout the South Island.
All hope of eradication of the invasive organisim were abandoned several years ago.
But has it turned out to be the major problem once feared and why hasn't it spread to the North Island?
The preventative Check Clean Dry programme is still being promoted, but is there any point?
Philippa Tolley has visited the Waitaki River area on the border between Otago and Canterbury, to find out more.